Hmm... maybe you're right. Because my friend got it as well. But he says his computer can't run it.

EDIT: I just figured out what it is. Steam is letting everyone play the game for free this weekend.

But I think my friend was legitimately gifted it because he received it around Tuesday. That, or it just showed up and he couldn't play it until this weekend. But mine didn't show up until either today or yesterday.